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1.\" Copyright (c) 2005 Pascal Gloor <pascal.gloor@spale.com>
2.\"
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27.\" $FreeBSD: src/lib/libc/string/memmem.3,v 1.3 2005/11/24 06:56:21 ru Exp $
28.\"
29.Dd August 24, 2005
30.Dt MEMMEM 3
31.Os
32.Sh NAME
33.Nm memmem
34.Nd "locate a byte substring in a byte string"
35.Sh LIBRARY
36.Lb libc
37.Sh SYNOPSIS
38.In string.h
39.Ft "void *"
40.Fo memmem
41.Fa "const void *big" "size_t big_len"
42.Fa "const void *little" "size_t little_len"
43.Fc
44.Sh DESCRIPTION
45The
46.Fn memmem
47function
48locates the first occurrence of the byte string
49.Fa little
50in the byte string
51.Fa big .
52.Sh RETURN VALUES
53If
54.Fa big_len
55is smaller than
56.Fa little_len ,
57if
58.Fa little_len
59is 0, if
60.Fa big_len
61is 0 or if
62.Fa little
63occurs nowhere in
64.Fa big ,
65.Dv NULL
66is returned;
67otherwise a pointer to the first character of the first occurrence of
68.Fa little
69is returned.
70.Sh SEE ALSO
71.Xr memchr 3 ,
72.Xr strchr 3 ,
73.Xr strstr 3
74.Sh CONFORMING TO
75.Fn memmem
76is a GNU extension.
77.Sh HISTORY
78The
79.Fn memmem
80function first appeared in
81.Fx 6.0 .
82.Sh AUTHORS
83.An Pascal Gloor Aq pascal.gloor@spale.com
84.Sh BUGS
85This function was broken in Linux libc up to and including version 5.0.9
86and in GNU libc prior to version 2.1.